Cast wall with modular units

ABSTRACT

A cast wall system comprising at least two modular units, each having a front surface, a back surface, and opposing edge surfaces. A first edge surface (e.g., an upper edge surface) of one modular unit is positioned adjacent to a second edge surface (e.g., a lower edge surface) of another modular unit. A compression system (e.g., a threaded rod under tension) and coupled to elongated beams) provides a force to compress the first edge surface of the one modular unit toward the second edge surface of the other modular unit, and a hardened backing (e.g., concrete) is positioned on the back surface of the at least two modular units. Preferably, the first and second edge surfaces are ground in order to improve the surface contact between those two edge surfaces. When producing the cast wall, the hardened backing is preferably poured onto the back of the modular units. Prior to and during the pouring, it is preferred to support a first end of the one modular unit and a second end of the other modular unit on a common rail. In one embodiment, the common rail includes a base portion and an upright portion (e.g., a T-rail), and the step of supporting includes positioning the base portion on a support surface, and setting the first end of the one modular unit and the second end of the other modular unit on the upright portion. Preferably, the second end of the one modular unit and the first end of the other modular unit are supported on rails different than the common rail.

FIELD OF THE INVENTION

The present invention generally relates to the field of concrete wallshaving veneered surfaces.

BACKGROUND

Due to the expense of building a conventional brick wall from brick,block, stone, or other hard modular unit, veneered building panels witha hardened backing (e.g., concrete) arc becoming more popular inbuilding construction. In one common process, thin modular units, suchas thin bricks or blocks, are laid out face down, and a concrete backinglayer is poured into the track of the units to form a cast wall. Theveneered brick building panels can either be pre-cast (i.e., constructedoff-site and then transported to the building site) or tilt up(constructed on-site and tilted up into place) to be attached to anexterior wall.

In the past, simulated brick veneered building panels were made of thinmodular units that are arranged on an object retention liner. U.S. Pat.No. 5,268,137 to Scott, et al. shows an object retention form liner thatholds and transfers objects, such as thin bricks, to the finishedsurface of concrete structures. Thin bricks are placed in recesses inthe form liner. Concrete is poured into the form liner to completelycover the backs of thin bricks. The concrete fills the spaces along thesides of the thin bricks and additional cavity areas to simulate thegrout line in conventional masonry construction. Once the concrete hasproperly hardened, the wall is raised and the form liner can be pulledaway from the outer surface of the concrete wall to expose the outersurface of the bricks having grout lines to give the appearance of aconventional masonry construction.

U.S. Pat. No. 5,009,387 to Scott, et al. shows a form liner withrecesses that are closely sized to fit the face of a standard brick or athin brick that is about one-half the depth of a standard brick. Therecesses are arranged in staggered rows in the surface of the form linerto resemble the normal grout line between bricks. Ridges between thebricks fill the area around each side of the brick to a desired depth toform the grout recesses. Retainers such as clips hold the bricks inposition in their individual recesses. The retainers are flexible andresilient enough to maintain proper spacing between bricks by absorbingthe vibration that occurs during the cement pouring process.

SUMMARY

Although the systems described above increase efficiency in theconstruction of walls, the thin modular units do not effectivelytransfer compressive loads. Therefore, the thin modular units are notable to be taken into account while measuring the load bearingcapabilities and structural rigidity of the wall. The result is that thepoured concrete must be sufficiently thick to take the full design loadof the wall. In addition, some existing pre-cast systems allow concreteto leak between the modular units and into the front face of the modularunits and onto the casting deck.

A need exists for a precast wall that is load bearing and can add to thestructural rigidity of the wall. A precast wall whereby the concretemodular units act as an integral structure and where the concretemodular units absorb and transfer a compressive load to each other willallow the precast wall to be calculated as a load bearing structure. Inaddition, there is a need for a precast system that inhibits the leakageof concrete onto the front face of the modular units.

The present invention provides a cast wall system comprising at leasttwo modular units, each having a front surface, a back surface, andopposing edge surfaces. A first edge surface (e.g., an upper edgesurface) of one modular unit is positioned adjacent to a second edgesurface (e.g., a lower edge surface) of another modular unit. Acompression system (e.g., a threaded rod under tension and coupled toelongated beams) provides a force to compress the first edge surface ofthe one modular unit toward the second edge surface of the other modularunit, and a hardened backing (e.g., concrete) is positioned on the backsurface of the at least two modular units. Preferably, the first andsecond edge surfaces are ground in order to improve the surface contactbetween those two edge surfaces.

The above-described cast wall system can be produced by positioning thefirst edge surface of the one modular unit adjacent to the second edgesurface of the other modular unit, compressing the first edge surfacetoward the second edge surface, and pouring a backing (e.g., concrete)on the back surface of the at least two modular units. Preferably, themethod also includes grinding the first and second edge surfaces priorto compressing.

In another aspect, the invention provides an improved method of forminga cast wall system that is made up of at least two modular units, eachmodular unit having at least a first end and a second end, and each endhaving an edge surface. The method comprises positioning an edge surfaceof the first end of one modular unit adjacent an edge surface of thesecond end of the other modular unit, supporting the first end of theone modular unit and the second end of the other modular unit on acommon rail, and pouring a backing (e.g., concrete) onto the modularunits. In one embodiment, the common rail includes a base portion and anupright portion (e.g., a T-rail), and the step of supporting includespositioning the base portion on a support surface, and setting the firstend of the one modular unit and the second end of the other modular uniton the upright portion. Preferably, the second end of the one modularunit and the first end of the other modular unit are supported on railsdifferent than the common rail.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear perspective view of a tray and cast wall with a portionbroken away.

FIG. 2 is a perspective view of a load-bearing modular unit shown inFIG. 1.

FIG. 3 is a cross-section view of the cast wall taken along line 3-3 inFIG. 1.

FIG. 4 is a close-up view of the cross-section of the cast wall shown inFIG. 3.

FIG. 5 is a rear perspective view of a second embodiment of a cast wallwith a portion broken away.

FIG. 6A is a perspective view of a first type of a load-bearing modularunit shown in FIG. 5.

FIG. 6B is a perspective view of a second type of a load-bearing modularunit shown in FIG. 5.

FIG. 7 is a cross-section view of the cast wall taken along line 7-7 inFIG. 5 with a portion of the concrete removed for clarity.

FIG. 8 is a close-up view of the cross-section of the cast wall shown inFIG. 7.

FIG. 9 is a section view of a third embodiment of the present invention.

FIG. 10 is an enlarged end view of a T-rail used in the embodiment ofFIG. 9,

FIG. 11 is a section view of a fourth embodiment of the presentinvention.

FIG. 12 is a section view of a fifth embodiment of the presentinvention.

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

DETAILED DESCRIPTION

FIG. 1 illustrates a veneered building panel, or a cast wall 10,embodying the present invention. The cast wall 10 includes load-bearingmodular units 14, inserts 18 coupled to some of the modular units 14,and connection bars 22 extending between the inserts 18. The cast wall10 can be either pre-cast, in which case the cast wall 10 is constructedoff-site and then transported to the building site, or tilt up, in whichcase and the cast wall 10 is constructed on-site and tilted up intoplace. Whether the cast wall 10 is pre-cast or tilt up, the constructionof the cast wall 10 is generally the same for both cases.

In constructing the cast wall 10, a frame 24 having the dimensions ofthe desired cast wall 10 is placed on a generally horizontal surface,such as the ground. The frame 24 can be constructed of many different ofmaterials, including without limitation steel, wood, rigid plastic, andother types of synthetic or non-synthetic materials, and any blend orcombination thereof. The frame 24 should be rigid to withstand any shearor normal forces that may be present once the modular units 14 areplaced inside the frame 24 and the concrete backing is poured.

The modular units 14 illustrated in FIGS. 1-4 are constructed ofconcrete. However, in other embodiments of the invention, the modularunits 14 can be constructed of various materials or combinations ofmaterials, including brick or stone. Most of the modular units 14 have acommon rectangular size like the unit shown in FIG. 2, but the cast wall10 also includes smaller modular units 27 to facilitate the constructionof a rectangular wall using a staggered pattern. Each modular unitincludes a rear surface 26 and a front surface 28 that may includesurface roughness or contours not present on the rear surface 26. Thefront surface 28 and the rear surface 26 are connected by four edgesurfaces 30. In the embodiment shown in FIGS. 1-4, the edge surfaces 30are smaller in area than the front surface 28 and the rear surface 26.

The edge surfaces 30 of the modular units 14 are qualified, or ground,to provide surfaces that will effectively mate with adjacent edgesurfaces for transfer of loads. More specifically, in the illustratedembodiment, the top and bottom edge surfaces 30 are ground so that theyare substantially parallel to each other, and the side edges are groundso that they are substantially parallel to each other and perpendicularto the top and bottom surfaces. Edge surfaces 30 that are not in contactwith other surfaces can function properly without grinding. For example,the top edge 34 and left edge 38 of the modular unit 42 at the top leftcorner of the cast wall 10 may function properly without being ground.

The front surfaces 28 of the illustrated modular units 14 are commonlycolored to provide a desired appearance. For example, the front surface28 can be colored and textured to provide the appearance of brick,granite, and other building materials. The color of the modular unitscan be mixed throughout the modular units or, alternatively, can be atthe surface only.

Referring to FIGS. 2 and 3, the front corners 29 of each modular unit 14are chamfered to give the appearance of a mortar joint when abutted nextto another modular unit 14. In the illustrated embodiment, thechamfering is accomplished by grinding the sharp corners, but thechamfering could also be molded into the modular unit 14 or formed inany suitable manner. When combined with surface coloring, the grindingoperation will expose the underlying material, which is commonly agray-colored concrete, resulting in the appearance of a mortar jointhaving a color different than the front surface 28 of the modular unit14.

In the embodiment illustrated in FIGS. 1-4, a top row 46 and a bottomrow 50 of modular units 14 of the cast wall 10 have a groove 54 formedin the rear surface 26. In other embodiments, variations in the locationand amount of grooves 54 can occur. The groove 54 is precision groundinto the modular units 14 and is toleranced square to the edge surfaces30 of the modular unit 14. As illustrated in FIGS. 2-4, thecross-section of the groove 54 is rectangular with rounded ends 62. Inother embodiments, the groove 54 can be square, cylindrical, oval,elliptical, triangular, or any other suitable shape.

The insert 18 includes a tongue portion 66, a stabilizer portion 70, anda receiving portion 74. The tongue portion 66 is dimensioned to fitsecurely into the groove 54. In the embodiment illustrated in FIGS. 1-4,the shape of the tongue portion 66 is cylindrical with rounded ends 78,similar to the groove 54. The illustrated tongue portion 66 is slightlysmaller than the groove 54 to achieve a snug fit. The size of the tongueportion 66 can be the same as the groove 54 to yield a press-fit forinsertion, or the size of the tongue portion 66 can be slightly largerthan that of the groove 54 to yield an interference-fit, depending onthe material of the insert 18. The insert 18 of the embodiment of theinvention illustrated in FIGS. 1-4 is metal. However, in otherembodiments, the material of the insert 18 can include, but is notlimited to steel, iron, ceramic, plastic or polymer materials, or acombination of such materials.

The stabilizer portion 70 is coupled to the tongue portion 66 and isdesigned to be positioned flush with the rear surface 26 of the modularunit 14 when the tongue portion 66 is inserted into the groove 54. Thestabilizer 70 serves to inhibit excess bending of or torque on theinsert 18 when the insert 18 is coupled to the connection bar 22. In theembodiment illustrated in FIGS. 1-3, the stabilizer 70 is generallyflat, circular, and of a larger size than the receiving portion 74 andtongue portion 66. In other embodiments, the stabilizer 70 can be of adifferent shape, size, or thickness to inhibit bending or excess torqueof the insert 18.

As illustrated in FIG. 1, the receiving portion 74 of the insert 18 iscylindrical in shape and has a flat circular face 82 and a cylindricaledge 86. In other embodiments, the shape of the receiving portion 74 canbe square, rectangular, oval, elliptical, triangular or any suitableshape. In the embodiment illustrated in FIGS. 1-4, upper and lowerapertures 90, 94 are present in the receiving portion 74. In theembodiment illustrated in FIGS. 1-4, the upper apertures 90 in theinserts along the top row 46 of modular units 14 are not threaded andthe lower apertures 94 in the inserts 18 along the bottom row 50 ofmodular units 14 are threaded. The size of each lower aperture 94 islarge enough to receive a first end 106 of a connection bar 22. Thefirst end 106 of connection bar 22 is threaded to screw into thethreaded lower aperture 94. A second end 114 of the connection bar 22 isnot threaded and has a stopper 110. The stopper 110 is of a size largerthan that of the upper aperture 90. In the embodiment illustrated inFIGS. 1-4, the stopper 110 is a threaded nut. In other embodiments, thestopper 110 can be welded or otherwise secured to the second end 114 ofthe connection bar 22. In other embodiments, both apertures 94, 90 canbe threaded in opposite directions to provide insertion of a connectionbar 22 having two threaded ends 106, 114 within the apertures 94, 90,respectively. Alternatively, both of the apertures 94, 90 can be smooth,while both ends 106, 114 of the connection bar 22 can be threaded withthreaded nuts securing the connection bar 22 through the apertures 94,90.

In constructing the cast wall 10 illustrated in FIG. 1, the modularunits 14 with ground edge surfaces 30 are placed inside the frame 24 andarranged in staggered rows. The modular units 14 placed in the top row46 and the bottom row 50 have grooves 54 for receiving the inserts 18.The inserts 18 can be placed in the modular units 14 prior to beingplaced in the frame. Alternatively, the inserts 18 can be placed in thegrooves 54 of the modular units 14 after the modular units 14 have beenarranged in the frame.

After the top row 46, bottom row 50, and middle rows 118 have beenarranged in the frame, the connection bars 22 can be installed. Asillustrated in FIG. 1, the first end 106 of the connection bar 22 isinserted through the aperture 94 in the insert 18 in the bottom row 50.The second end 114 of the connection bar 22 is inserted into theaperture 90 of the insert 18 in the top row 46 of modular units 14. Thestopper 110 is connected onto the second end 114 of the connection bar22, and the connection bar 22 is then rotated to engage the threads inthe aperture 94. The connection bar 22 is rotated until a desiredtension is achieved in the connection bar 22.

In embodiments wherein both ends 106, 114 of the connection bar 22 arethreaded and both apertures 94, 90 are threaded, a first end 106 of theconnection bar 22 is inserted into a first aperture 94 and the secondend 114 of the connection bar 22 is inserted into a second aperture 90.Because the first aperture 94 is threaded opposite to that of the secondaperture 90, when the connection bar 22 is rotated, both ends 106, 114of the connection bar 22 will engage the respective threads and therebytighten and compress the cast wall 10. In this embodiment, theconnection bar 22 can be threaded partially into the inserts 18 beforethe inserts 18 are engaged with the grooves 54.

In other embodiments of the invention wherein both ends 106, 114 of theconnection bar 22 are threaded and the apertures 94, 90 are notthreaded, the first end 106 of the connection bar 22 can be insertedinto a first aperture 94 independent from or simultaneously with thesecond end 114 of the connection bar 22 being inserted into a secondaperture 90. Stoppers 110 can then be screwed onto the threaded ends106, 114 of the connection bar 22 until the modular units 14 arecompressed. Other methods of compressing the modular units 14 areavailable in alternative arrangements of the connection bar 22 andinserts 18.

After compressing the modular units 14 with the connection bar 22,concrete 88 is poured into the frame 24 and onto the back of theassembled modular units 24. The concrete 88 is evenly spread on the rows46, 50, 118 of modular units 14. The concrete 88 sits for a time perioduntil the concrete 88 is hardened to a desired drying point. The castwall 10 can then be tilted up to be used as a structural building wall.It should be understood that any other suitable hardened backing can beused instead of concrete.

Another embodiment of the invention is shown in FIGS. 5-8. FIG. 5illustrates a veneered building panel, or a cast wall 210, made up ofload-bearing modular units 214 having a similar arrangement to the castwall 10 illustrated in FIGS. 1-4. Analogous to the cast wall 10 of FIGS.1-4, the cast wall 210 of FIGS. 5-8 can be either pre-cast or tilt up inconstruction. The illustrated modular units 214 are constructed ofconcrete, but can be constructed of other materials or variouscombinations of material as described for the modular units 14 of FIGS.1-4. The modular units 214 also have a similar shape, edgecharacteristics, corner design, and surface features as the modularunits 14 of the embodiment illustrated in FIGS. 1-4. The cast wall canalso include smaller modular units 227, similar to the smaller modularunits 27, to facilitate the construction of a rectangular cast wall 210using a staggered pattern.

The modular units 214 have chamfered edges 229 that are aligned with thechamfered edges 229 of the adjacent modular unit 214. In the embodimentillustrated in FIGS. 5-8, the chamfered edges 229 are squared off toform a rectangular chamfer. In other embodiments, the chamfered edges229 can be round, oval, beveled, triangular, or square.

The chamfered edges 229 allow for a U-shaped chair, or riser 236, to beinserted into the chamfered edges 229. The riser 236 has two arms 240that each fit within the chamfered edge 229 of a modular unit 214. Abase portion 244 of the riser 236 rests on a flat surface 245 (e.g., theground G) within a frame 252. As illustrated in FIGS. 7-8, a frontsurface 256 of the modular units 214 is not entirely smooth. The risers236 allow for the modular units 214 to be at an equal height off theground, or other flat surface, and aligned with one another duringconstruction of the cast wall 210. The illustrated risers 236 include asolid base portion 244 that helps to capture any concrete that may leakbetween the joints and keep the concrete off of the casting deck. In analternative embodiment, the base portion 244 can be semi solid.

In the embodiment illustrated in FIGS. 5-8, the modular units 214 arearranged in the frame 224 similar to the embodiment illustrated in FIGS.1-4. The modular unit 214 for insertion into a top row 246 or a bottomrow 250 of the cast wall 210 is illustrated in FIG. 6A. The modular unit214 has a horizontal groove 254 formed in a rear surface 226, similar tothe groove 54 of the illustrated embodiment of FIGS. 1-4. The horizontalgroove 254 is precision ground to be parallel to the top and bottomedges 256. The modular unit 214 shown in FIG. 6A also has a set ofvertical grooves 326, 330 formed in the rear surface 226 that extendperpendicular to the horizontal groove 254. The modular unit 214 (shownin FIG. 6B) used for middle rows 318 of the cast wall 210 also hasvertical grooves 326, 330. One vertical groove 326 is locatedone-quarter of the length of the modular unit 214 in from a firstparallel side edge 334 of the modular unit 214. The other verticalgroove 330 is located one-quarter of the length of the modular unit 214in from a second parallel side edge 338 of the modular unit 214. Asshown in FIG. 5, when the modular units 214 are arranged into staggeredrows, a top edge 342 of a first modular unit 346 contacts one half of alower edge 350 of second and third modular units 354, 358. One verticalgroove 326 of the first modular unit 346 is aligned with a verticalgroove 330 of the second modular unit 354, and the other vertical groove330 of the first modular unit 346 is aligned with a vertical groove 326of third modular unit 358.

As illustrated in FIGS. 7-8, an L-shaped elongated beam 218 is insertedinto the groove 254 of the top row 246 such that a first face 220 of theelongated beam 218 engages a bottom sidewall 221 of the groove 254. Asecond face 222 of the elongated beam 218 engages a back wall 223 ofhorizontal groove 254. Another elongated beam 218 is inserted into thebottom row 250 such that a first face 220 of the elongated beam 218engages a top side wall 225 of the horizontal groove 254, and a secondface 222 engages the back wall 223 of the horizontal groove 254. Inother embodiments, the first face 220 of the elongated beam 218 canengage the bottom sidewall 221 and the second face 222 can engage therear surface 226 of the modular units 214 of the top row 246. Likewise,for the bottom row 250, the first face 220 can engage the top sidewall225 of the horizontal groove 254, and the second face 222 can engage therear surface 226 of the modular units 214. With any arrangement of theelongated beam 218, adhesive (e.g., epoxy—not shown) can be addedbetween any surface of the modular unit 214 and the elongated beam 218to keep the elongated beam 218 from moving prior to concrete 288 beingpoured onto the rear surface 226 of the cast wall 210.

The elongated beam 218 has apertures 294 that are spaced to align withthe grooves 326, 330. The apertures 294 are located on either the firstface 220 or the second face 222 of the elongated beam 218, depending onwhich face 220, 222 is adjacent the grooves 326, 330. The apertures 294are large enough to receive a first end 306 or a second end 314 of theconnection bar 322. The first end 306 and second end 314 of theconnection bar 322 are threaded and can be connected to a threaded nut310. In other embodiments, variations in the connection between theelongated beam 218 and the connection bar 322 can exist as long as theconstruction allows for compression of the modular units 214 by theconnection bar 322.

The cross-section of the connection bar 322 illustrated in FIGS. 5 and7-8 is generally round. The vertical grooves 326, 330 for receiving theconnection bar 322 are of a round shape, or a shape that can fullyaccommodate the round connection bar 322. In other embodiments, theshape of the connection bar 322 and grooves 326, 330 can vary. Thehorizontal groove 254 has a more squared shape to receive at least oneface 220, 222 of the elongated beam 218. However, the horizontal groove254 can be shaped in various ways to receive alternative shapes of thefaces 220, 222 of the elongated beam 218.

In constructing the cast wall 210 of FIG. 5, the modular units 214 arearranged in the frame 224 in staggered rows 246, 250, 318. The too row246 and bottom row 250 include the modular units 214 having the verticaland horizontal grooves 254, 326, 330 (shown in FIG. 6A), and the middlerows 318 include the modular units 214 having only the vertical grooves226, 330 (shown in FIG. 6B). The connection bars 322 are placed in thealigned vertical grooves 326, 330 such that the first end 306 and thesecond end 314 of the connection bar 322 extend into horizontal grooves254 of the top and bottom rows 246, 250. One of the elongated beams 218is placed into the horizontal groove 254 of the top row 246 of modularunits 214 such that the first end 306 of the connection bar 322 isreceived within the corresponding aperture 294 of the elongated beam218. The second elongated beam 218 is placed into the horizontal groove254 of the bottom row 250 of modular units 214 to receive the bottom end314 of the connection bar 322 within the corresponding aperture 294 ofthe elongated beam 218. Other variations and sequences for constructingthe cast wall 210 are possible.

Upon the connection bar 322 being fully inserted within the verticalgrooves 326, 330 of the modular units 214 and into the apertures 294 inthe elongated beams 218, the threaded nuts 310 can now be screwed ontothe first or second ends 306, 314 of the connection bar 322 to cause theconnection bar 322 to compress the modular units 214 together. When themodular units 214 are compressed by the connection bar 322 to thedesired force, the cast wall 210 is ready for concrete 288 to be poured.The concrete 288 is not shown to be entering grooves 326, 330 of castwall 210 in FIGS. 7-8 for purposes of clarity and viewing of theinteraction between components of the assembled cast wall 210. However,in practice, concrete 288 will seep into the grooves 326, 330. Theconcrete 288 sits for a time period until the concrete 288 is at aspecific drying point, similar to the cast wall 10 illustrated in FIGS.1-4. The cast wall 210 is then tilted up to be used as a structuralbuilding wall.

In should be understood that the vertical compression of the modularunits structurally integrates the modular units as a structuralcomponent of the building wall, and further inhibits leakage of concretebetween the top and bottom edges of adjacent modular units. The modularunits can also be compressed in the horizontal direction in order toinhibit the leakage of concrete between the side edges of adjacentmodular units. Because the side edges are precision ground, horizontalcompression of the modular units will provide the desired seal to deterconcrete leakage. The horizontal compression is not illustrated in thedrawings, but can be performed in a manner similar to that describedabove for the vertical compression. For example, the horizontalcompression can be performed using an apparatus similar to thatillustrated in FIGS. 1-4 (with appropriate vertical slots formed in themodular units), and the vertical compression can be performed using theapparatus of FIGS. 5-8. Alternatively, the horizontal compression can beperformed using a carpenter's pipe clamp engaging the side edges of eachrow.

In one embodiment, the horizontal compression is performed first,followed by the vertical compression. After the vertical compression isadded, the apparatus for creating the horizontal compression can beremoved. Due to the overlapping nature of the modular units, thevertical compression will maintain at least a portion of the horizontalcompression. In this manner, only the apparatus that creates thevertical compression will be embedded into the concrete backing.

In a modification of this embodiment, a small vertical compression isapplied first, followed by horizontal compression of each row (eithersimultaneously or sequentially). The horizontal compression of each rowis strong enough to overcome the friction created by the verticalcompression and move the units horizontally into intimate contact witheach other. The horizontal compression is then removed, and the smallvertical compression will hold the units in place. Concrete can then bepoured into the back of the assembled units.

In another embodiment of the invention, the compression of the units canbe performed by the frame 24. More specifically, the side rails of theframe can be designed to be movable so that a compressive force can beapplied by the rails on the assembled units. For example, a pipe clampcan be applied to force the rails into contact with the units, or someother system (e.g., manual, hydraulic, pneumatic, etc.) can be used tomove the rails and apply a compressive force to the units.

FIG. 9 illustrates a third embodiment of the present invention includinga cast wall 400 having a mixture of split face blocks 402 and smoothface blocks 404 (for clarity, the blocks 402,404 are not shown insection) and a concrete backing 405. As with the previously-describedembodiments, the system of FIG. 9 utilizes a frame 406 that forms theouter periphery of the cast wall 400. In addition, the illustratedsystem is design to work with modular units having ground edges.

The embodiment of FIG. 9 utilizes a compression system that applies acompressive force to the blocks. The illustrated compression systemincludes L-shaped beams 410 and threaded compression rods 412 (forclarity, the rod 412 is not shown in section). The L-shaped beams 410fit into horizontal grooves 414 in the blocks, and one leg 416 of eachbeam 410 extends beyond the back surface 418 of the correspondingmodular unit. The long leg 416 of each beam 410 is provided with a hole(not shown) that receives a compression rod 412, which positions the rod412 slightly spaced from the back surface 418 of the modular units. Thisalleviates the need for the vertical grooves in the back surface of themodular units.

The embodiment of FIG. 9 further includes T-rails 420 in place of theriser 236 of the previous embodiment. Referring to FIG. 10, each T-rail420 includes a base portion 422 having a width W1 of about 1.50 inchesand an upright portion 424 having a height H of about 1.188 inches fromthe bottom of the base portion 422. The upright portion 424 of theillustrated T-rail 420 includes a narrow section 426 having a width W2of about 0.19 inches and a wide section 428 having a width W3 of about0.31 inches. Referring back to FIG. 9, a series of T-rails 420 are usedto support the edges of the modular units. On each end of the wall 400adjacent the frame 406, L-rails 430 are used to support the end of thetop and bottom rows of modular units.

FIG. 11 shows the use of the compression system concept of the presentinvention with a more conventional cast brick system (for clarity, theconcrete backing is omitted from FIG. 11). The illustrated system willproduce a cast wall 500 having three rows of split face block 502 on thetop, six rows of brick 504 in the middle, and one row of split faceblock 506 on the bottom (for clarity, the blocks 502,504,506 are notshown in section). The top three rows of block 502 are set up in themanner described above with respect to FIGS. 9 and 10. The rows of brickare set using a foam riser 508 that supports brides having brick snaps510 to reduce concrete leakage between the bricks 504, as is known inthe art. The bottom row of block 506 is supported on rails 512, but novertical compression is applied. With the system of FIG. 11, the blocks502,506 and bricks 504 can be integrated into the same wall, and therelative depths of the blocks 502,506 and bricks 505 can be adjusted bychanging the heights of the rails 512 and the foam riser 508.

FIG. 12 illustrates application of some of the concepts of the presentinvention to a cast wall 600 that is formed upside down from theconventional manner. More specifically, in the embodiment of FIG. 12,the concrete 602 is poured into the frame 604 before the blocks 606 areset in place. The blocks 606 are then place right side up onto theconcrete 602 with an appropriate compression system. In this embodiment,the threaded rods 608 (for clarity, the threaded rod 608 is not shown insection) of the compression system are accessible through tubes 610 thatextend through holes in the sidewall of the frame 604 and engage thebeams 612. Due to the close fit of the frame 604, the rods 608, thetubes 610, and the beams 612, only a small amount of concrete is likelyto leak out of the holes in the frame 604.

Thus, the invention provides, among other things, a cast wall having aveneered surface that is load bearing and able to transfer compressiveloads. The invention further provides a system for building a cast wallwherein the amount of concrete leaking between the modular units isreduced. In addition, the invention provides a rail system that supportsthe modular units while a backing is being poured. Various features andadvantages of the invention are set forth in the following claims.

1. A cast wall system comprising: at least two modular units, eachmodular unit having a front surface, a back surface, and opposing edgesurfaces, wherein a first edge surface of one modular unit is positionedadjacent to a second edge surface of another modular unit; a compressionsystem providing a force to compress the first edge surface of the onemodular unit toward the second edge surface of the other modular unit;and a hardened backing distributed on the back surface of the at leasttwo modular units.
 2. The cast wall system of claim 1, wherein the firstedge surface is an upper edge surface and the second edge surface is alower edge surface.
 3. The cast wall system of claim 1 wherein the firstedge surface is a left side edge surface and the second edge surface isa right side edge surface.
 4. The cast wall system of claim 1, whereinthe first edge surface comprises a ground surface.
 5. The cast wallsystem of claim 1, wherein both the first and second edge surfacescomprise ground surfaces.
 6. The cast wall system of claim 1, whereinthe compression system includes a connection bar under tension.
 7. Thecast wall system of claim 6, wherein the connection bar comprises athreaded rod.
 8. The cast wall system of claim 6, wherein thecompression system further includes an elongated beam coupled to atleast one modular unit and coupled to the connection bar.
 9. The castwall system of claim 1, wherein the hardened backing comprises concrete.10. A method of forming a cast wall system, the cast wall system made upof at least two modular units, each modular unit having a front surface,a back surface, an upper edge surface, and a lower edge surface, themethod comprising: positioning a first edge surface of one modular unitadjacent to a second edge surface of another modular unit; compressingthe first edge surface of one modular unit toward the second edgesurface of the other modular unit; and pouring a backing on the backsurface of the at least two modular units.
 11. The method of claim 10,further comprising grinding the first edge surface prior to compressing.12. The method of claim 10, further comprising grinding both the firstand second edge surfaces prior to compressing.
 13. The method of claim10, further comprising supporting a portion of each modular unit on acommon rail.
 14. The method of claim 10, wherein compressing includesforcing the modular units toward each other.
 15. A method of forming acast wall system, the cast wall system made up of at least two modularunits, each modular unit having at least a first end and a second end,each end having an edge surface, the method comprising: positioning anedge surface of the first end of one modular unit adjacent an edgesurface of the second end of the other modular unit; supporting thefirst end of the one modular unit and the second end of the othermodular unit on a common rail; and pouring a backing onto the modularunits.
 16. The method of claim 15, wherein the common rail includes abase portion and an upright portion, and wherein supporting includes:positioning the base portion on a support surface; and setting the firstend of the one modular unit and the second end of the other modular uniton the upright portion.
 17. The method of claim 15, wherein the commonrail is a first rail, and wherein the method further comprises:supporting the second end of the one modular unit on a second rail; andsupporting the first end of the other modular unit on a third rail. 18.The method of claim 15, wherein the backing comprises concrete, andwherein the method further includes hardening the concrete.